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Bovine mastitis is a cause of major financial losses in the dairy industry worldwide. Bovine mastitis is defined as the inflammatory response of the udder tissue due to either physical trauma or infections caused by different microorganisms, especially bacteria. More than 135 pathogenic agents have been identified from bovine mastitis. The aim of the study was to identify the bacterial genera involved in mastitis etiology in cattle and to test the antimicrobial susceptibility to antibiotics. The samples were collected before morning milking and evaluated by microscopic and cultural examination, and further identified using biochemical methods. The evaluation of antimicrobial susceptibility was performed using Kirby-Bauer disk diffusion test. Overall, Staphylococcus spp., Bacillus spp., Streptococcus spp., Micrococcus spp., Escherichia spp. and Trueperella spp. were identified. The most frequent bacterial associations were observed for Staphylococcus-Bacillus, Bacillus-Streptococcus and Staphylococcus-Micrococcus. Regarding the antimicrobial sensitivity profile, the majority of the bacterial strains we have isolated were classified as sensitive, with the exception of Escherichia coli, with one strain being resistant to all tested antibiotics. Among the antimicrobials, the Amoxicillin and clavulanic acid was the most efficient one and Trimethoprim/Sulfamethoxazole did not exhibit an inhibitory activity in 19 milk samples.

Goat mastitis is still frequently diagnosed in dairy farms, with serious consequences on milk quality and composition. The aim of this study was to establish correlations between milk microorganisms and biochemical parameters in goats with no signs of clinical mastitis. Thus, 76 milk samples were collected from a dairy goat farm, Carpathian breed, followed by microbiological, molecular (16S rRNA sequencing) and somatic cells analysis, determination of lactate dehydrogenase (LDH), β-glucuronidase, catalase (CAT), glutathione peroxidase (GPx) activity, total antioxidant capacity (TAC), nitric oxide (NO) and lipid peroxides (LPO) using spectrophotometry and the ELISA method for 8-hydroxy-deoxyguanosine (8-OHdG) as the oxidative DNA damage indicator. Samples positive for bacterial growth showed a significant (p < 0.05) increase in the number of somatic cells, LDH and β-glucuronidase activity, as well as higher levels of CAT, GPx, NO, LPO and 8-OHdG compared with pathogen-free milk whereas TAC was lower in milk from an infected udder. These findings suggest that subclinical mastitis is associated with increased enzymatic activity and induction of oxidative stress. Nevertheless, changes in biochemical parameters tended to vary depending on the pathogen, the most notable mean values being observed overall in milk positive for Staphylococcus aureus.

The present study aimed to assess the in vitro antimicrobial effects of a novel biomaterial containing polylactic acid (PLA), nano-hydroxyapatite (nano-HAP) and Doxycycline (Doxy) obtained by electrospinning and designed for the non-surgical periodontal treatment. The antimicrobial activity of two samples (test sample, PLA-HAP-Doxy7: 5% PLA, nano-HAP, 7% Doxy and control sample, PLA-HAP: 5% PLA, nano-HAP) against two periodontal pathogens—Aggregatibacter actinomycetemcomitans and Porphyromonas gingivalis—was assessed using the Kirby–Bauer Disk Diffusion Susceptibility Test and compared with the effect of four antibiotics used as adjuvants in periodontal therapy: Amoxicillin, Ampicillin, Doxy and Metronidazole. The test sample (embedded with Doxy) showed higher inhibitory effects than commonly used antibiotics used in the treatment of periodontitis, while the control sample showed no inhibitory effects. Moreover, significant differences were observed between the inhibition zones of the two samples (p < 0.05). The Doxy-loaded PLA nanofibres had an antimicrobial effect against the periodontal pathogens. Based on these results, the novel biomaterial could be a promising candidate as adjuvant for the non-surgical local treatment in periodontitis.

Goat milk ranks fourth in terms of global milk production and lately it has become increasingly popular among consumers. Unfortunately, mastitis is one of the most common diseases that affects dairy goats, with serious economic consequences and food safety matters. The prevalence of clinical mastitis is lower than 5% and the main aetiological agent is S. aureus. On the other hand, the prevalence of subclinical mastitis is between 5-30%, with coagulase negative staphylococci (CNS) representing the most often isolated microorganisms. The aim of this paper is to highlight the main aspects regarding the aetiology of goat mastitis, as well as the importance of the milk somatic cell count (MSCC) in the diagnosis process. Although the inflammation of the mammary gland in goats is not as frequently diagnosed compared to cow mastitis, there are several aspects worth discussing in order to fully understand the pathogenesis of intramammary infections.

Due to their unique properties, nano-polyoxometalates (POMs) can be alternative chemotherapeutic agents instrumental in designing new antibiotics. In this research, we synthesized and characterized “smart” nanocompounds and validated their antibacterial effects in order to formulate and implement potential new drugs. We characterized thirty POMs in terms of antibacterial activity–structure relationship. The antibacterial effects of these compounds are directly dependent upon their structure and the type of bacterial strain tested. We identified three POMs that presented sound antibacterial activity against S. aureus, B. cereus, E. coli, S. enteritidis and P. aeruginosa strains. A newly synthesized compound K6[(VO)SiMo2W9O39]·11H2O (POM 7) presented antibacterial activity only against S. aureus (ATCC 6538P). Twelve POMs exerted antibacterial effects against both Gram-positive and Gram-negative strains. Only one POM (a cluster derivatized with organometallic fragments) exhibited a stronger effect compared to amoxicillin. New studies in terms of selectivity and specificity are required to clarify these extremely important aspects needed to be considered in drug design.

The conjunctival bacterial resident and opportunistic flora of dogs may represent a major source of dissemination of pathogens throughout the environment or to other animals and humans. Nevertheless, contamination with bacteria from external sources is common. In this context, the study of the antimicrobial resistance (AMR) pattern may represent an indicator of multidrug resistant (MDR) strains exchange. The present study was focused on a single predisposed breed—Saint Bernard. The evaluated animals were healthy, but about half had a history of ocular disease/treatment. The swabs collected from conjunctival sacs were evaluated by conventional microbiological cultivation and antimicrobial susceptibility testing (AST). The most prevalent Gram-positive was Staphylococcus spp.; regardless of the history, while Gram-negative was Pseudomonas spp.; exclusively from dogs with a history of ocular disease/treatment. Other identified genera were represented by Bacillus, Streptococcus, Trueperella, Aeromonas and Neisseria. The obtained results suggest a possible association between the presence of mixed flora and a history of ocular disease/treatment. A high AMR was generally observed (90%) in all isolates, especially for kanamycin, doxycycline, chloramphenicol and penicillin. MDR was recorded in Staphylococcus spp. and Pseudomonas spp. This result together with a well-known zoonotic potential may suggest an exchange of these strains within animal human populations and the environment.

In recent years, essential oils (EOs) have received increased attention from the research community, and the EOs of cinnamon, patchouli, and geranium have become highly recognized for their antibacterial, antifungal, antiviral, and antioxidant effects. Due to these properties, they have become valuable and promising candidates for addressing the worldwide threat of antimicrobial resistance and other diseases. Simultaneously, studies have revealed promising new results regarding the effects of physical fields (magnetic and electric) and LASER (MEL) exposure on seed germination, plant growth, biomass accumulation, and the yield and composition of EOs. In this frame, the present study aims to investigate the influence of MEL treatments on cinnamon, patchouli, and geranium EOs, by specifically examining their composition, antimicrobial properties, and antioxidant activities. Results showed that the magnetic influence has improved the potency of patchouli EO against L. monocytogenes, S. enteritidis, and P. aeruginosa, while the antimicrobial activity of cinnamon EO against L. monocytogenes was enhanced by the electric and laser treatments. All exposures have increased the antifungal effect of geranium EO against C. albicans. The antioxidant activity was not modified by any of the treatments. These findings could potentially pave the way for a deeper understanding of the efficiency, the mechanisms of action, and the utilization of EOs, offering new insights for further exploration and application.

Contagious sheep footrot is an infectious disease with chronic evolution, usually enzootic, characterized by necrotic or necrotic-purulent inflammation of the soft tissues of the hoof, which causes partial or total detachment of the horn. Cu-based products represented by (I) 1-hydroxyquinoline + Cu on 5% hydroxyapatite, (II) 2 Hydroxyquinoline + Cu + NO3 on 5% Hydroxyapatite and (III) 3 Nitrohydroxyquinoline + Cu on 5% Hydroxyapatite were conditioned in aqueous suspension in a volume of 100 ml, pH 6,0 – 6,4. The products were placed into wells, 20 μL/well, along with 0.5 % copper sulphate solution (Cu control) and Enroxil and Oxitetracycline (control for antibiotics). The results demonstrated that 7 of the samples (58.33 %) are sensitive to the product I, 6 samples (50%) to the product III, 4 samples (33.33 %) to the product 2 and the 0.5% Copper sulphate solution only has a bacteriostatic effect. In comparison to the two antibiotics, 9 samples (75 %) are sensitive to enrofloxacin and only 5 samples (41.66 %) to oxytetracycline. Regarding the associations of microorganisms in the samples with resistance, we have found that these are represented by the most common germs of genus Bacillus, Corynebacterium and Gram negative bacteria, and rarer associations with Micrococcus and Staphylococcus.

Mastitis is a complex and well-defined mammary gland pathology, and an emergency in bitches. In dogs, its prevalence is about 1% of all reported diseases and about 5.3% of all reproductive pathologies. Lactating bitches are naturally prone to developing mastitis since puppies can easily overstimulate the epidermal layer of nipples during feeding, facilitating bacterial colonization of the glands. This study aimed to describe the aerobic bacterial flora isolated from milk samples derived from a cohort of patients (n = 87) diagnosed with clinical mastitis (n = 29), subclinical mastitis (n = 17) and healthy mammary glands (n = 46). All of the patients underwent a gynecology consultation to diagnose mammary gland afflictions; physical examination results were coupled with traditional hematological findings. The milk samples were plated on specific microbiological media for bacterial isolation. Among the 162 milk samples analyzed, 93.2% (151/162) had a positive microbiological result, while 6.8% (11/162) were sterile. The bacteriological profile of the milk samples showed 47 different species. The most common bacterial families detected in healthy bitches and bitches with subclinical and clinical mastitis were the Staphylococcaceae, Enterobacteriaceae and Enterococcaceae families. The results indicated that half of the isolated bacteria are novel findings in dogs and that some of them are normal components of human milk.

Abstract: In March 2016, the microbiology laboratory of the Faculty of Veterinary Medicine in Cluj-Napoca, 3 type of antisalmonella vaccine for sheep were prepared. For type 1, 24 hours salmonella on brain heart infusion (BHI) broth culture, heat inactivated for 1 hour at 60°C, then with formaldehyde in a concentration of 3 ‰. Variant 2 - the culture supernatant obtained on solid BHI medium, washed with PBS, frozen-thawed 6 times, centrifuged at 4000 rpm for 15 minutes, filtered through 0.2 μm Millipore filter Orange Scientific. Variant 3 - suspension of cell walls remaining after centrifugation suspended in PBS and inactivated with formaldehyde. After the bacterial and fungal sterility control, the three types of vaccine were administered in rabbits by the subcutaneous route at a dose of 1 ml/individual along with 1 ml of plant extract adjuvant (decoction of Ewernia prunastri) sterilized by filtration. There have been two booster inoculations of the initial administration, 7 and 14 days after. Before each dose of vaccine, blood was sampled from the marginal auricular vein in order to control the immunogenicity by anti-somatic ˮOˮ serum antibody (Ab) titration using slow microplate agglutination test (Widal reaction). After three inoculations with the vaccine variant 1, Ab serum titer reached 1/128, and in types 2 and 3, 1/512 after 2 inoculations, decreasing to 1/256 after the second booster administered with no immunomodulator.

The aim of the present study was to investigate the antibacterial activity of propolis samples collected from various regions in Transylvania (Romania) against six bacterial strains: three Gram-positive bacteria (Staphylococcus aureus ATCC 6538P, Bacillus cereus ATCC 14579, Listeria monocytogenes ATCC 7644), two Gram-negative bacteria (Escherichia coli ATCC 10536, Pseudomonas aeruginosa ATCC 27853) and one yeast strain (Candida albicans ATCC 90028). Ethanolic extracts of the studied samples were prepared for the evaluation of antimicrobial activity, which was appreciated by measuring the inhibition zones diameters. The methodology used was agar diffusion technique inside Petri dishes with nine wells. Enroxil was used as control. A better sensibility of the Gram-positive bacteria (Staphylococcus aureus, Bacillus cereus, Listeria monocytogenes) was noticed; the diameter of the inhibition zones ranged between 8 mm and 17 mm. As for Gram-negative bacteria, results were different for every tested bacterial strain. Inhibition zones diameter for E. coli ranged between 7 mm and 12 mm, while for P. aeruginosa a total resistance was noticed. Inhibition zones diameters for Candida albicans showed a variation which ranged between 0 mm and 10 mm. Minimum inhibitory concentration (MIC) was evaluated for sample PS 20 due to the positive results showed against Staphylococcus aureus. According to the results obtained, it might be concluded that the tested propolis samples showed good results against Gram-positive bacteria.

This study is aiming to evaluate the antimicrobial activity of ten essential vegetal extracts on strains of Staphylococcus aureus isolated from animal lesions. The comparative effect of some antibiotics on these strains isolated from animals was also tested and estimated. The extracts were represented by Albies alba, Aloe barbadensis, Calendula officinalis, Cocos nucifera, Eucalyptus globulus, Hypericum perforatum, Lavandula angustifolia, Satureja hortensis, Mentha piperita, Pinus silvestris essential oils, in three amounts (30 μl, 3 μl and 0,3 μl) and comparatively eight antibiotics frequently utilized in staphylococci infections treatment in animals were used. Animal origin S. aureus strains were identified using API staph tests (BioMerieux, France). The tests were realized by diffusion method using Muller Hilton agar while the antibacterial effect was interpreted depending on the inhibition area diameter. The obtained results revealed that Satureja hortensis and Albies alba extracts inhibit the develop of the most staphylococci tested strains. The highest inhibition areas were observed for the amounts of 30 μl and 3 μl essential extract. Most of the staphylococci strains were resistant to antibiotics, the most efficient being Ceftiofur and Methicillin. The results are suggesting that savory and fir has antibacterial effect on S. aureus similar to the best antibiotics proving to be an alternative as natural antibiotics utilization in infectious diseases.

Prototheca is a unicellular, achlorophillous, ubiquitary and saprophytic alga spread in the surrounding environment mostly in vastly damp locations in the presence of the organic matters. This is deemed to be pathogenic to a low degree, taking immediate advantage of the environment and triggering diseases at a time when the immunological capability of defense of the organisms is low or, when favorable factors come about. Prototheca is capable to induce disease in man as well as in several other animal species. Twenty strains of Prototheca sp, were sampled from cows with mastitis. The strains are characterized morphologically and developmentally on various culture media: glucose media (broth and agar), blood agar, potato medium, glucose medium of various pH values, medium containing antibiotics, Mac Conkey agar, Smith Baskerville medium (without antibiotics), and engine-oil medium. Growth took place within conditions of aerobic at 37 C and the culture became visible within 36-48 hours. On liquid media there has been noticed that the medium keeps settled and the tube bottom shelters granular drags, that lend to slight homogenization. On solid media the colonies become visible within 36-48 hours. By continuing to maintain them at room temperature, they increase in size. First, they are small, irregular in shape resembling ice crystals reflecting shiny irisations. With lapse of time, they increase in size reaching 3-5 mm, displaying pale-white colour. They also increase in height and the surface takes a mulberry or cauliflower shape. Morphological assessment was carried out on wet smear in Lol solution or in thinned staining solutions (methylene blue, malachite green, Congo red or fuchsine), allowing for good differentiation in the inner structures. The prevailig shape of Prototheca is that of an egg, seldom round or, that of a kidney with variation in size between 9.5/10.5?m up to 27.5/30.4?m. With some cells 6 to 8 endospores were noticed. Based on morphological and cultural characters there was set down that the strains under surveillance belonged to the species of Prototheca zopfii.